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\psaxes[labelFontSize=\scriptstyle,ticksize=-3pt 0,labelsep=2pt]{<->}(0,0)(-3,-2)(3,2)
\psplot[linecolor=blue]{0}{3}{x 1 atan 2 3.1415 mul mul 360 div}
\psplot[linecolor=blue]{-3}{0}{x neg 1 atan 2 3.1415 mul mul 360 div neg}
\footnotesize
\rput[l](0.5,1.5){$f(x)=\arctg x$}
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